# SperaxOS ERC-8004 Agent Attestation Validation Check

> SperaxOS ERC-8004 Agent Attestation Validation Check is a paid API for AI agents from chat.sperax.io, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-19).

Checks whether a specific ERC-8004 attestation type is valid for a given on-chain agent token ID on a testnet blockchain

## Facts

- Endpoint: POST https://chat.sperax.io/api/x402/tools/erc8004/checkValidation?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/speraxos-erc-8004-agent-attestation-validation-check-8783a6d7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_yHXGOMOw3Z6UmrMvn4CLM

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability speraxos-erc-8004-agent-attestation-validation-check-8783a6d7 -d '<json body>'
```

Example prompt: Check whether agent token ID 42 on BSC testnet has a valid identity attestation according to ERC-8004.

## When to prefer this

Use this endpoint when you need to programmatically verify whether a specific on-chain agent (identified by ERC-8004 token ID) holds a valid attestation of a particular type (identity, capability, security, or compliance) on a supported testnet. Prefer this over manual on-chain lookups when building automated agent-to-agent trust workflows or DeFi access control checks that require attestation verification.

## Known failure modes

- Invalid or non-existent agent token ID returns not-found or invalid result
- Unsupported blockchain network (only bsc-testnet and sepolia are supported) causes error
- Unrecognized attestation type may return null or error
- Payment of 0.001 USDC via x402 not provided causes 402 Payment Required response
- Network connectivity issues to the target testnet RPC may cause timeouts

## How this service works

AI-powered DeFi intelligence APIs payable via the x402 HTTP payment protocol. No API key required — pay per request with USDC on Base. Identity-only (SIWX) endpoints are free for wallets with an agentcash identity.

## Output

Returns the validation status indicating whether the specified ERC-8004 attestation type (e.g. identity, capability, security, compliance) is currently valid for the given agent token ID on the specified testnet blockchain.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "chain": {
   "type": "string",
   "default": "bsc-testnet",
   "description": "Blockchain to query (testnet only: bsc-testnet, sepolia)"
  },
  "agentId": {
   "type": "string",
   "description": "The token ID of the agent"
  },
  "attestationType": {
   "type": "string",
   "description": "The attestation type to check (e.g., identity, capability, security, compliance)"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/speraxos-erc-8004-agent-attestation-validation-check-8783a6d7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from chat.sperax.io](https://www.zero.xyz/host/chat.sperax.io/llms.txt)